Bisecting plane rotary motion transmission device

ABSTRACT

This invention relates to a constant velocity universal joint including a drive shaft, a driven shaft and means interconnecting the shafts for relative swinging movement of the axes of said shafts from 0* to more than 90*. Said means comprising two semi circular forks, a yoke carried on the adjacent end of each of said shafts, a bevel gear carried by each shaft within said fork, a ring mounted for rotation about a diameter of said ring that coincides with the diameter of an articulation of said forks, and pinion gears mounted to rotate on said ring and mesh with said bevel gears.

United States at Feb. 5, 1974 [76] Inventor: Andre Rene Rey, 93, Rue dela Curveillere, Albi, France 22 Filed: Apr. 20, 1972 21 Appl. No.:245,874

[30] Foreign Application Priority Data May 4, 1971 France 71.16717 [52]U.S. Cl. 64/21, 64/17 R [51] lnt. Cl. lFl6d 3/30 [58] Field of Search64/21, 18, 17

[56] References Cited UNITED STATES PATENTS 3,456,458 7/1969 Dixon 64/211,899,170 2/1933 Wainwright 64/21 5/1962 Morgenstem 64/21 6/1970 Eccher64/21 Primary Examiner-Charles J. Myhre Assistant ExaminerRandall HealdAttorney, Agent, or Firm Young & Thompson [57] ABSTRACT This inventionrelates to a constant velocity universal joint including a drive shaft,a driven shaft and means interconnecting the shafts for relativeswinging movement of the axes of said shafts from 0 to more than 90.Said means comprising two semi circular forks, a yoke carried on theadjacent end of each of said shafts, a bevel gear carried by each shaftwithin said fork, a ring mounted for rotation about a diameter of saidring that coincides with the diameter of an articulation of said forks,and pinion gears mounted to rotate on said ring and mesh with said bevelgears.

1 Claim, 6 Drawing Figures PATENTEU FEB 1 74 SHEET 1 M 3 PATENTEU FEB 3.789 625 BISECTING PLANE ROTARY MOTION TRANSMISSION DEVICE SUMMARY Theobjective of the present invention is to construct a me chanical systemfor the transmission of rotary motion permitting the coupling of adriving shaft to a driven shaft with concurrent geometric axes and to obtain a speed of rotation for both shafts that is always equal, even whenthe angle formed by the geometric axes of the shafts varies from tobeyond 90.

This objective is attained when the points connecting the two shafts areon the same plane which bisects the angle of their geometric axes andwhen the bisecting plane is the plane of symmetry of the system.

The two shafts are joined by: two yokes mounted on the end of each shaftand two forks sliding in the yokes. These forks are connected to eachother on their merged diameters by articulated assembly.

The displacements of the parts in relation'to one another are such thatthe geometric axes of the shafts form angles which are variable from 0to beyond 90.

A circular ring, which materialises the bisecting plane, is placedinside the forks and fixed to them by an articulated assembly in such away as to bring its diameter into coincidence with the diameter of theforks.

On the inside of the ring, a cross turns, carrying two bevel wheelsconnected to the yokes and two other bevel pinions engaging with thefirst two.

The cross and bevel wheel assembly revolves freely inside the ring, and,through the equality of the wheel engagement sectors, this assemblytakes a position such that it compels the ring to merge with thebisecting plane for all values of the angle of the geometric axes of theshafts.

The system is symmetrical in relation to the bisecting plane; therotation speeds of the two shafts are equal.

DESCRIPTION The present invention consists of a device for thetransmission of rotary motion from a driving shaft to a driven shaft, ofwhich the geometric axes are concurrent and form a variable angle.

There are various known types of devices for the transmission 'of rotarymotion which comprise a driving shaft and a driven shaft with their endsfixed to either side of a flexible plate which, through its deformation,communicates the rotary motion from one shaft to the other when theirgeometric axes intersect forming a variable angle. These already knowndevices are little used and they lack precision. For example, the angleof the geometric axes of the two shafts varies from 0 to a maximum ofapproximately and the rotation speed of the driven shaft varies inrelation to the rotation speed of the driving shaft. In other knowndevices, the driving shaft and the driven shaft are connected to a crossmade up of two integral and perpendicular arms.

However, these devices have several disadvantages, for example: theangle of the two geometric shaft axes varies from 0 to a maximum ofapproximately 40. Moreover, if the driving shaft moves at a uniformrotation speed, the driven shaft moves at a rotation speed that variesperiodically.

The present invention permits the avoidance of the disadvantages of theknown devices while aiming at a rotary motion transmission device whichcommunicates the rotary motion from a driving shaft to a driven shaftwith concurrent axes and an angle varying from 0 to more than withoutinterrupting the rotary motion.

Another objective is a driven shaft that always moves at the same speedof rotation as the driving shaft.

The apparatus of the present invention comprises a driving shaft and adriven shaft with concurrent geometric axes and means at the end of eachshaft designed to join the shafts at several connecting points and toplace and maintain these connecting points on a plane that is bothperpendicular to the plane of the geometric shaft axes and a bisector ofthe angle of these axes, in order to transmit the motion of one shaft tothe other with equal speed of rotation for both shafts, while the angleof their geometric axes varies from 0 to beyond 90.

In a realisation of the invention, these means are constituted by: twosemicircular forks attached, on one hand, by articulated connections ontheir diameters at two points on the outside periphery of a ring suchthat the diameters of the forks coincide, and, on the other hand,connected by a sliding assembly along their semicircular arcs, each witha single yoke in an assembly of two yokes such that one is integral withthe driving shaft and the other is integral with the driven shaft: twoidentical cylindrical spindles with concurrent and perpendiculargeometric axes, forming a cross with four equal arms, the four ends ofwhich are set to turn inside the ring. The said cross carries twoidentical bevel pinions turning on two opposing arms and, turning on theother two opposing arms, two bevel wheels which are and remain identicalto each other, each carrying a cylindrical arm with geometric axisperpendicular to the wheel axis, with the said arm resting and turningin a bore that is integral with each yoke. The geometric axis of eachcylindrical arm coincides with the axis of the bore on the yoke and theaxis of the shaft corresponding to the yoke. This device ischaracterised by the fact that the geometric axis common to the plane ofthe driving and driven shafts and that the four bevel wheels engage witheach other in such a way that the axis of the pinions that are notequipped with cylindrical arms is compelled to bisect the angle formedby the axes of the driving shaft and the driven shaft.

The following more complete and detailed description, as well as theappended figures to which it refers, as a non-restrictive example, showsall the characteristics and advantages of the present invention, whichrelates to a preferred but non-exclusive means of realisation of abisecting plane rotary motion transmission device in conformity with theinvention.

FIG. 1 is an elevation view of the device.

FIG. 2 is a sectional view of the device on a plane perpendicular to theplane of FIG. 1, which it cuts along AA.

FIG. 3 is a sectional view of the device on a plane BB parallel to theplane of FIG. 1 and cutting the plane of FIG. 2 along BB.

FIG. 4 is a sectional view of the device on the same plane 'AA as inFIG. 2, the system having made a quarter turn in relation to FIG. 1,with the driving and driven shafts forming angle a.

FIG. 5 is a partial diagrammatic view of the system for comprehension ofits operation.

FIG. 6 is also a partial diagrammatic view of the system forcomprehension of its operation.

A driving shaft 1 with geometric axis ZY and a driven shaft 2 withgeometric axis RP, in extension of one another in FIGS. 1,2,3,5 andintersecting at 90 in FIGS. 4,6.

A yoke 8 integrally fixed to the shaft 1 -by a weld 20, for example anda yoke 9 fixed to shaft 2, also by a weld 20. These yokes are identical,each possessing a similar plane of symmetry and axis of symmetry. Theplane of symmetry of yoke 8 coincides with the plane of FIG. 1 and theaxis of symmetry of this yoke 8 coincides with the geometric axis ZY ofshaft 1. The plane of symmetry of yoke 9 coincides with the plane ofFIG. 1 the axis of symmetry of this yoke 9 coincides with the axis RP ofshaft 2.

In addition, the said yokes possess internal faces F FIGS. 2,3 parallelto their respective planes of symmetry.

A fork 3, semicircular (FIGS. 2,3) and with section M FIG. 2 in the formof a rectangle with two consecutive corners slightly beveled, axis Z Ybeing the me: dian of the long sides of the rectangle of section M. Thisfork possesses a plane of symmetry which con tains its diameter ST andwhich is parallel to all its radii, while coinciding with the plane ofFIG. 1. This diameter ST is perpendicular to axis RPYZ, which it intersects at point K, the middle of said diameter ST.

The undepicted radius of fork 3, originating at point K, the middle ofST, and coinciding with axis ZY, is the axis of symmetry of this fork 3.

Another fork 4 (FIGS. l,2,3,4) identical to the preceding also possessesa plane of symmetry which con- 9 tains its diameter VX and which isparallel to all its radii, while coinciding with the plane of FIG. 1.This diameter VX is perpendicular to axis RPYZ, which it intersects atthe above defined point K, the middle of diameter VX. The undepictedradius of fork 4, originating at point K and coinciding with geometricaxis RP is the axis of symmetry of this fork 4. Fork 3 is equipped withtwo ball races W (FIGS. 1,2) grooved along the semicurlar profile of thefork on its parallel faces corresponding to the short sides of therectangle of.

section M. H

This fork 3 is assembled with yoke 8, which has ball races W grooved onits internal faces F identical to those on fork 3. The two parts areconnected by balls (FIG.3) mounted in a cage plate 16 (FIGS.l,2) whichallows them to turn about their centres while preventing them fromcoming out of the races W.

In the same way that fork 3 is assembled with yoke 8 fork 4 is assembledwith yoke 9.

Fork 4 has two holes bored on its diameter V,X in order to receive aneedle socket 6 assembled. in each bore with no play FIGS. 1,3. Inaddition ,the extremities of the said fork 4 have thickness Ex equal tohalf their thickness Eg.

Similar to fork 4, fork 3 is bored to receive two needle sockets 6.

In addition, the extremities of this fork 3 have thickness Ex equal tohalf their thickness Eg.

Parts Ex of fork 4 are tangential to its inside diameter di. Parts Ex offork 3 are tangential to its outside diameter (de).

The two forks 4 and 3 are in contact on faces F which are perpendicularto axes S,T and V,X.

Two pins D and E with outside diameters corresponding to the insidediameter of needle sockets 6, are mounted inside the saidsockets,assembling forks 3 and 4.

Surface Et (FIGS.l,3) of fork 3 never comes into contact with surface E0of fork 4; the same is true of surfaces Er of fork 4 and surfaces Es offork 3.

After this assembly, diameter ST of fork 3 coincides with diameter VX offork 4.

A circular ring 7 (FIGS.1,2,3,4,5,6) possessing a plane of symmetry Biparallel to all these diameters and perpendicular to axis RPYZ which itintersects at point K, the centre of the diameters of the ring 7. Thisring 7 receives ,on its outside periphery at the two ends of a diameterlocated on plane Bi, the two cylindrical connecting pins D, E, ofwhichthe geometric axes coincide with the said diameter, of the ring.

Fork 3 (FIG.3) is connected to ring 7 in such a way that the diameter STof this fork coincides with the diameter of the ring that carriescylindrical pins D and E. Washers 21 interposed between the sockets andring ensures an assembly with no play.

Similarly, fork 4 (FIG.2) is connected to ring 7 with its diameter VXcoinciding with the diameter of the ring 7, which carries cylindricalpins D and E. This connection is also made by means of sockets 6 andwashers 21.

A cross (10)(FIGS.5,6) is constituted by two equal cylindrical spindlesjoined in the middle in such a way that their geometric axes areperpendicular and they form four equal arms .11, J2, J3, J4.

The two geometric axes of the cross arms 10 are on the crosss plane ofsymmetry. This cross 10 is assembled inside ring 7 by means of fourballs 15 (FIGS.2,3,4) placed, on the one hand,in four hemisphericalcavities hollowed out of the end of each arm of the cross 10 and,on theother hand,in a ball race W grooved on the inside of the ring along itsplane of symmetry.This assembly is realised in such a way that theplanes of symmetry of the ring and the cross coincide.

A bevel wheel 11 (FIGS.1,3) possesses an arm BR with a cylindricalextremity, the geometric axis of this cylindrical extremity beingperpendicular to the geometric axis of the bevel wheel 11.

On yoke 9 inside the semicircle of fork 4, a bracket 17 (FIGS. .2,3) isfixed by screws 19, for example. This bracket contains a bore withgeometric axis coinciding with the geometric axis of yoke 9 and shaft 2.

The bevel wheel 11 is mounted on cross spindle J1, about which it canturn. The cylindrical arm BR on the bevel wheel 11 is assembled withyoke 9 by means of the bore in bracket 17, as arm BR is equipped with aball race on a plane perpendicular to its geometric axis and the bracketbore is equipped with an identical ball race .Arm BR is thereforeimprisoned in the bracket bore,within which it can turn. The geometricaxes of cylindrical arm BR, the bore in bracket 17 yoke 9 and shaft 2coincide.

A bevel wheel 12 (FIGS.l,2,3,4) identical to the preceding is mounted oncross spindle .13, about which it can turn. Bevel wheel 12 possesses acylindrical arm BR identical to the above with geometric axisperpendicular to the axis of wheel 11. This arm is assembled with yoke 8by means of a bracket 18 (FIGS.l,2,3,4) identical to bracket 17 andfixed to yoke 8 by screws 19. Balls hold cylindrical arm BR inside thebore in bracket 18. The geometric axes of arm Br, the bore in bracket18, yoke 8 and shaft 1 coincide.

Wheels 11 and 12 have their teeth face to face, turned toward the centreof the cross and they are coaxial.

A bevel pinion 13 turns on cross spindle J2 (FIGS.2,4) and a bevelpinion 14 turns on cross spindle J4. Their teeth are face to face,turned toward the inside of the cross. Wheel 11 engages with pinions 13and 14 and wheel 12 engages with pinions l3 and 14.

A geometrical study of the system shows that the apparatus of thepresent invention operates in the following manner:

Initially and at rest, the geometric axes ZY and RP of shafts 1 and 2merge in an extension of one another,the system being in the positiondefined by FIGS. 1,2,3 and 5 and the above description.

A torque applied to shaft 1 causes it to rotate about its geometric axisZY. The yoke is driven by shaft 1. This yoke causes fork 3 to turn aboutaxis ZY, while remaining immobile in relation to the yoke 8. Fork 3causes ring 7 to rotate about axis ZY. The plane of symmetry of the ringcontaining two long diameters is compelled to remain perpendicular toaxis ZY, since the axes of the cross spindles are themselves compelledto remain perpendicular to axis RPYZ because of the bevel wheels,whichare perpendicular to axis RPYZ. The ring 7 causes fork 4 to rotatearound axis RPYZ,- communicating the rotary motion to yoke 9,whichbrings shaft 2 into rotation about axis RP. The assembly of cross 10 andbevel wheels 11, 12, 13, 14 is not put into motion, as it can turnfreely and independently inside ring 7 and the brackets 17, 18 fixed tothe yokes 9, 8.

The plane of symmetry of the ring Bi (FIGS.1,2,3,5),- which isperpendicular to axis RPYZ,is the bisector of the angle formed by thegeometric axes of shafts 1 and 2. On this plane ofsymmetry,shafts l and2 are joined at two connecting points located upon the geometric axes ofpins D E,and the diameters ST and VX of forks 3, 4.

Since the system is symmetrical in relation to the plane of symmetry ofthe ring,the rotation speed of shaft 1 is equal to the rotation speed ofshaft 2.

In a second operation,let us consider the system having made a quarterturn in relation to the initial position defined by FIGS. 1, 2, and 3,and the descriptionFlG.4 and 6,with no torque applied to shafts l and2.Let us displace shaft 2 (FIGS.4,6),while maintaining its geometricaxis RP on the plane which contains it and which is perpendicular to theplane of FIG. 1,which it cuts along RPYZ,until axis RP forms an angle aof 90 with axis ZY.This is a non-restrictive example,as the angle a ofthe two axes RP and ZY can vary from the 0 to beyond 90. Axes RP and ZYintersect at K.

As soon as axes RP of shaft 2 and ZY of shaft 1 form an angle other than0 ,axis ST (FIGS.1,3) of bevel wheels 11 and 12 and spindles J1 and J3of the cross 10 places and maintains itself in a position perpendicularat K (FIG.6) to the plane of the axes RP ZY of shafts 1 and 2,since theaxis of wheels 11 is on a plane perpendicular at K to the axis RP ofshaft 2 and the axis of wheel .12 is on another plane which is alsoperpendicular at K to axis ZY of shaft 1.Since the axes of wheels 11 and12 coincide, they are located at the intersection of the planesperpendicular at K to each axis RP, ZY,this intersection being theperpendicular at point K to the plane of the axes RP and ZY of shafts 2and 1.

Consequently,the axis of pinions 13 and 14 is on the plane of theconcurrent axes RP and ZY.The cross occupies a well determined positionwith its centre at K. The axis of spindles J1 and J3 is perpendicular tothe plane of the two axes RP and ZY,the other geometric axis of spindlesJ2 and J4 being on the said plane RP, ZY. The above-mentioneddisplacement of shaft 2 provokes the rotation of bevel wheel 11 FIG.6 onits cross arm spindle J1.The other wheel 12, (FIGS.4,6) remains immobileon its spindle J3.

Pinions 13 whose axes are shown at (10), and 14 are put into motion bywheel 11 in such a way that if one considers FIG.6 the primitivediameters D11 D12 and D13 of wheels 11, 12 and 13,without representingpinion 14,pinion 13 engages with the same number of teeth or the samefraction thereof with wheel 11 and wheel 12.

The tangential points of circles D11, D12 and D13 being 22 and 23 whenRP and ZY are in a straight line FIG.5,and 24 and 25 when RP isdisplaced (FIG.6) the lengths of arcs 22, 24 (FIG.6) of circle D13 and22 24 of D11 and 25, 23 of D13 and 25 23 of D12 are equal.

Consequently,axis VX common to pinions 13 and 14 is on the plane of RPand ZY and bisects the angle a formed by these two geometric axes RP andZY.

As the axis RP of shaft 2 is displaced on the plane which contains itand which is perpendicular to the plane of FIG. 1, which it cuts alongRPYZ,yoke 9 slides on fork 4 (FlG.4),itself put into motion on plane RP,ZY by its diameter VX,which coincides with the axis of pinions 13 and14.Fork 3 is driven by its diameter and slides in yoke 8.

The two connecting points of shafts 1 and 2,located on the geometricaxes of pinsD and E are on the same plane Bi that bisects the angle a ofaxes RP and ZY.

The system being in the position of FIG. 4,a torque is applied to shaft1,causing it to turn about its axis ZY and drive yoke 8,which causesfork 3 to turn about axis ZY.The diameter ST of this fork beingcompelled to remain on plane Bi,it slides in yoke 8.The ring 7 is putinto rotary motion in relation to its centre K. Fork 4 is driven by pinsD and E.The diameter VX of fork 4 being compelled to remain on planeBi,this fork slides on yoke 9 while rotating about geometric axis RP.Thecircular motion is transmitted to yoke 9 and shaft 2,which is driven ina rotary motion about its geometric axis RP.

The rotation speeds of driving shaft 1 and driven shaft 2 at an angle dof are 'equal, the system being symmetrical in relation to plane Bi.

The description of the system and the study of its operation lead to theunderstanding that the angle a of the two geometric axes ZY and RP ofdriving shaft 1 and driven shaft 2 can have a lesser or greater valuethan 90.

The device resulting from the present invention can be used for allcases in which the transmission of a rotary motion must be effectedbetween two connected shafts forming variable and mobile angles in spaceand rotating at the same speed within the scope of general mechanics andconstruction of all devices using bevel gear flexible couplings andflexible shafts.

Particulary useful applications could be the fabrication of thetransmission of drive and steering wheels on automobile vehicles onwhich the inside turning wheel displaces up to 90.

As it is conceived, the invention may undergo numerous modifications andvariations which are all included within the bounds of its inventiveconception.

An element can be replaced by a technically equivalent element.

The dimensions and materials used for its implementation shall varyaccording to the requirements of each application.

I claim:

1. Apparatus for the transmission of rotary motion from a driving shaftto a driven shaft whose axes intersect, with equal speed of rotationwhen the angle between the axes varies from to more than 90, comprisingmeans interconnecting the shafts for relative swinging movement of theiraxes from 0 to more than 90, said means comprising two semi-circularforks disposed in the form of a complete circle and articulatedlyinterconnected about a diameter of that circle, a yoke carried on theadjacent end of each of said shafts, means mounting each saidsemi-circular fork for sliding movement in its plane in and relative toa said yoke, a shaft carried by each said yoke for rotation within saidforks about an axis that coincides with the axis of the drive or drivenshaft to which said yoke is secured, a bevel gear carried by each saidshaft within said fork and having an axis perpendicular to the axis ofthe associated said drive or driven shaft, a ring disposed within andmounted for rotation about a diameter of said ring that coincides withsaid diameter of articulation of said forks, and pinion gears mountedfor rotation on said ring and in mesh with said bevel gears.

1. Apparatus for the transmission of rotary motion from a driving shaftto a driven shaft whose axes intersect, with equal speed of rotationwhen the angle between the axes varies from 0* to more than 90*,comprising means interconnecting the shafts for relative swingingmovement of their axes from 0* to more than 90*, said means comprisingtwo semi-circular forks disposed in the form of a complete circle andarticulatedly interconnected about a diameter of that circle, a yokecarried on the adjacent end of each of said shafts, means mounting eachsaid semicircular fork for sliding movement in its plane in and relativeto a said yoke, a shaft carried by each said yoke for rotation withinsaid forks about an axis that coincides with the axis of the drive ordriven shaft to which said yoke is secured, a bevel gear carried by eachsaid shaft within said fork and having an axis perpendicular to the axisof the associated said drive or driven shaft, a ring disposed within andmounted for rotation about a diameter of said ring that coincides withsaid diameter of articulation of said forks, and pinion gears mountedfor rotation on said ring and in mesh with said bevel gears.